Do Calla Lilllies Have Bulbs?

Rhizomes

• Unlike fibrous root systems, calla lilies use a rhizome, or storage organ, for leaf and flower growth. Each rhizome has several bud growing points that allow each leaf to develop directly from the soil. These flowers do not have true stems for foliage and flower support because the rhizome itself is an underground stem. The leaves and flowers often rise to 3 feet tall in proper soil conditions. This vigorous growth only occurs when the rhizome has ample moisture and nutrients available. If nutrient conditions are poor, calla lilies simply rely on their stored energy until it can be restored through normal absorption.

Adaptation

• For most plants grown from a bulb-type root system, the underground organ must remain dry or slightly damp to avoid rot and nutrient deficiencies. Calla lilies thrive in soggy conditions. For example, plant these spectacular flowers along your pond's edge to complement any water flowers nearby. In some areas, calla lilies are considered invasive because of their ability to thrive in wet soil. If you cultivate your lilies in containers, it is critical to keep the pot's saucer full of water. The soil naturally uses capillary action to wick the water into the container through the drain holes to keep the plant constantly hydrated.

Planting Position

• For successful calla lily growth, select a partially shady spot for the rhizome in the spring. As you inspect the rhizome, find the buds or eyes on its surface. You need to plant the rhizome in a horizontal position so most of the buds face upward. Planted 3 inches deep, the developing foliage has no trouble breaking the soil surface to photosynthesize. Do not crowd your garden or container with closely spaced rhizomes -- maintain approximately 18 inches between rhizomes to prevent competition and to encourage new growth.

Maintenance

• To preserve your calla lilies over the winter, dig them from the garden and plant them in a container for indoor storage. Your container medium should be moistened periodically to maintain damp conditions. Although calla lilies may survive the winter in warmer climates, digging the rhizome stops cold damage and possible pest infestation. It also gives you a chance to divide the rhizome if bulblets become too numerous -- your lily cannot produce prolific blossoms with crowded roots.